Verification Events

To verify a user's phone number using the Verify API, you first make a verify request and receive the request_id.

The Verify API then sends a verification code to the user by SMS. When they enter the code into your application, you check the verification code by making a request to the Verify API using the request_id and the code the user provides.

If the user does not enter the code within the allowed time, the Verify API makes two further attempts to verify the user by making Text-to-speech (TTS) voice calls.

Note: You are limited to a maximum of one verify request per second.

Timing of each event

The following table shows the three events that are triggered and the amount of time the Verify API waits by default before triggering the next event. You can also trigger the next verification attempt programmatically.

Step Verification event Wait time before next event
1. Nexmo sends a verification code via SMS 125 seconds
2. Nexmo makes the first TTS call to read the code to the customer 180 seconds
3. Nexmo expires the first code and makes a second TTS call with a new code 300 seconds

If the user still has not responded after all three verification attempts, the verification process is unsuccessful.

To customize wait times and the duration after which verification codes expire, see changing the default event timings.